Authentication bypass via failed XML canonicalization
Published Aug 25, 2026 · Updated Aug 28, 2026
Unchecked return handling in Sparkle Motion Nokogiri 1.5.1 through 1.19.0 allows remote attackers to bypass SAML signature validation. The CRuby Document#canonicalize and Node#canonicalize methods ignore xmlC14NExecute failure and return an empty string instead of raising an exception. Downstream SAML validation that treats the empty result as valid can compute a digest over it and accept attacker-supplied XML; JRuby is not affected.
Summary
What happened
Unchecked return handling in Sparkle Motion Nokogiri 1.5.1 through 1.19.0 allows remote attackers to bypass SAML signature validation. The CRuby Document#canonicalize and Node#canonicalize methods ignore xmlC14NExecute failure and return an empty string instead of raising an exception. Downstream SAML validation that treats the empty result as valid can compute a digest over it and accept attacker-supplied XML; JRuby is not affected.
The record
- CVE
- CVE-2026-79772
- Published
- Aug 25, 2026
- Updated
- Aug 28, 2026
- Vendor
- Sparkle Motion
- Product
- Nokogiri
- Classifications
- CWE-252
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 25, 2026CVE publishedPublication date reported by the CVE source.
- Aug 28, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=1.5.1 <1.19.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Reported exploitation
- Downstream SAML signature-validation bypassreported exploitation
Technologies
Your stack
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Your stack
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